From 65aa909590463e2d19cb763c346c42296ef92ee6 Mon Sep 17 00:00:00 2001 From: jhb Date: Tue, 5 Nov 2013 19:54:35 +0000 Subject: [PATCH] MFC 253656: Enhance the description of NOTE_TRACK: - NOTE_TRACK has never triggered a NOTE_TRACK event from the parent pid. If NOTE_FORK is set, the listener will get a NOTE_FORK event from the parent pid, but not a separate NOTE_TRACK event. - Explicitly note that the event added to monitor the child process preserves the fflags from the original event. - Move the description of NOTE_TRACKERR under NOTE_TRACK as it is not a bit for the user to set (which is what this list pupports to be). Also, explicitly note that if an error occurs, the NOTE_CHILD event will not be generated. git-svn-id: svn://svn.freebsd.org/base/stable/8@257717 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- lib/libc/sys/kqueue.2 | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/lib/libc/sys/kqueue.2 b/lib/libc/sys/kqueue.2 index 326632d44..0f10da099 100644 --- a/lib/libc/sys/kqueue.2 +++ b/lib/libc/sys/kqueue.2 @@ -386,20 +386,25 @@ The process has called .It NOTE_EXEC The process has executed a new process via .Xr execve 2 -or similar call. +or a similar call. .It NOTE_TRACK Follow a process across .Fn fork calls. -The parent process will return with NOTE_TRACK set in the +The parent process registers a new kevent to monitor the child process +using the same .Va fflags -field, while the child process will return with NOTE_CHILD set in +as the original event. +The child process will signal an event with NOTE_CHILD set in .Va fflags and the parent PID in .Va data . -.It NOTE_TRACKERR -This flag is returned if the system was unable to attach an event to -the child process, usually due to resource limitations. +.Pp +If the parent process fails to register a new kevent +.Pq usually due to resource limitations , +it will signal an event with NOTE_TRACKERR set in +.Va fflags , +and the child process will not signal a NOTE_CHILD event. .El .Pp On return, -- 2.45.0